Effect Of Spraying Kinetin And Ethrel At Different Periods On Lodging-resistance Trait And Yield Of Maize

Test in JiuSan Farm in Heilongjiangin province in 2015~2016,selects the local maize varieties Demeiya No.1 and Demeiya No.2 as the test material.When maize grown 5,7 and 9 full leaf stage,sprayed promotional type of plant growth regulator Kinetin(KT)and retarding type of regulator Ethrel(ETH),with water as controls.Analysis of maize lodging resistance agronomic characters,lodging-resistance mechanics characteristics of stem and yield,prove by chemical constituents and related enzyme,to choose the regulator spraying period,to provide a scientific basis for summer maize improve the lodging-resistance and increase yield.Main results for this study are as follows:ETH sprayed on Demeiya No.1 and NO.2 on the 9-leaf stage plant height significantly reduced7.45% and 10.72%,increasing the internode diameter,effect of plant height,ear height and internode diameter than CK is better than that 5,7-leaf stage.KT treatment on plant height and ear height not remaekable effect.KT and ETH sprayed on both varieties on the9-leaf stage,internode density control effect is better than ETH treatment,treatment and CK stem diameter in harvest festival and the peroxidase(POD)activity as follow: ETH > KT > CK,indoleacetic acid oxida-se(IAAO)activity were higher than CK.KT and ETH sprayed on both varieties on the9-leaf stage has had improved the lodging-resistance of agronomic characters.KT sprayed on Demeiya No.1 on the 5-leaf stage,internode breaking strength than CK effect is better than that 7,9-leaf stage,increasing hemicellulose,cellulose,lignin,chemical composition,content and L-phenylalanine ammonia-lyase(PAL)activity of stalk.ETH sprayed on Demeiya No.1 on the 7-leaf stage,internode breaking strength was than that 5,9-leaf stage,showed greater reductions in lignin content and PAL.KT and ETH sprayed on 7-leaf stage than CK,effect of Demeiya NO.1 internode puncture strength was better than that 5,9-leaf stage,effect of Demeiya No.2 internode breaking strength and puncture strength increased was better than that 5,9-leaf stage.ETH treatment is better than KT.With KT and ETH sprayed on both varieties on 7-leaf stage for lodging resistance mechanics characteristics of stem.Both kinds of regulator after spraying,decrease the lodging rate of maize.KT sprayed on Demeiya No.1 on 9-leaf stage,lodging rate reduced 8.75%,ETH sprayed on Demeiya No.2 on7-leaf stage,lodging control reduced 10%.The results from path analysis indicated that the direct effect of internode diameter and PAL activity on lodging was most.KT sprayed on the 9-leaf stage,effect of seed characteristics of maize was best,both varieties grain number per ear increased 7.25%,yield significantly increased 22.24% and 19.98%.ETH sprayed on both varieties on 9-leaf stage,yield increased 4.67% and 9.4% but not remarkable.In short,effect of ETH was better on lodging-resistance,when it sprayed on 9-leaf stage,was best than others on lodging-resistance mechanics characteristics of stem but increase yield was not remarkable.KT sprayed on 9-leaf stage improved on lodging-resistance mechanics characteristics of stem,while increase yield was remarkable.